The goal of this project is to develop functional magnetic resonance imaging (fMRI) tools for assessing and treating human patients with a brain neoplasm or other focal pathology involving the visual system, especially visual cortex. Such patients can face difficult decisions balancing aggressive, invasive treatment of the pathology with side- effects involving partial or complete loss of vision. The core technology includes methods for creating a brain map of visual cortex function near a cancer site and linking this to a unique display technology, termed a Functional Field Map (FFMap). The latter allows the physician to easily interpret the fMRI activity patterns in terms of vision preservation/impairment and thereby assess the potential side effects of invasive treatment. Using a novel Visual Field Defect simulator, the patient can experience a simulation of potential vision loss that a particular treatment scenario might cause. These tools will aid diagnosis, treatment planning, and follow-up assessment for virtually any localized pathology, but especially cancer. Under this grant (and a subsequent Phase II proposal), the prototype system that currently exists in the Pi's lab will be optimized for clinical use and commercialization. Initial validation tests will be extended to verify the feasibility of commercialization. Proof of concept will be demonstrated by installing a test system in the Radiology Dept. of an affiliated hospital and using it to acquire, analyze and display data from patient volunteers having brain-based vision deficits. A team of experienced physicians including radiologists, neurosurgeons and radiation oncologists will assess the utility of the approach. Successful project completion will produce an installed and functioning prototype system with initial assessment of clinical utility. [unreadable] [unreadable]